A one step stunner method and apparatus therefor is disclosed in U.S. Pat. No. 4,694,534 to Lacy Simmons. The said patent is incorporated herein its entirety by reference.
The present invention is a modified version of the stunner of said patent. The stunner of Simmons operates with a pulsating low DC voltage. The lower voltage, usually in the 10-14 volt range for chickens, 14-18 volts for small turkeys, and 30-35 volts for larger turkeys. These voltages work very well for most processors; but are not acceptable for those localities requiring a "stun-to-kill".
In general, most stunners used outside North America are based upon a design developed in Western Europe. These European stunners operate as "water bath" stunners. This means that the birds's heads and necks are dragged through a tank of electrically charged water. This results in a very inconsistent stun, and, when combined with European style killing machines which cut only one side of the bird's neck, results in birds still being alive when reaching the scalder. This is the main reason that many European countries now require the "stun-to-kill" practice.
However, when a bird is killed in a stunner with electrical current, there is a very strong possibility of causing damage to the carcass such as broken bones and hemorrhaging of blood vessels. Poultry processors have been looking for alternative stunning methods to improve the "stun-to-kill" procedure so that the birds can be stunned with less resulting product damage.